Microphones: Polar pattern / Directionality

The polar pattern of a microphone is the sensitivity to sound relative to the direction or angle from which the sound arrives, or easier worded how well the microphone “hears“ sound from different directions. The most common types of directionality are: Omnidirectional, Cardioid and Supercardioid

Cardioid Polar Pattern

A cardioid microphone has the most sensitivity at the front and is least sensitive at the back. This isolates it from unwanted ambient sound and gives much more resistance to feedback than omnidirectional microphones. This makes a cardioid microphone particularly suitable for loud stages.

Cardioid microphones

Supercardioid Polar Pattern

Supercardioid microphones offer a narrower pickup than cardioids and a greater rejection of ambient sound. But they also have some pickup directly at the rear, hence it is important to place monitor speakers correctly. Supercardioids are most suitable when single sound sources need to be picked up in loud environments. They are very resistant to feedback.

Supercardioid microphones

Omnidirectional Polar Pattern

The omnidirectional microphone has equal sensitivity at all angles. This means it picks up sound evenly from all directions. Therefore, the microphone need not be aimed in a certain direction, which is helpful especially with lavalier microphones. A disadvantage is that an omni cannot be aimed away from undesired sources such as PA speakers, which results in less headroom for feedback.

Omnidirectional microphones

Bidirectional polar pattern

A microphone with a Figure of Eight polar pattern picks up the sound from in front of the microphone and from the rear, but not the side (at a 90 degree angle). Microphones with this Figure of Eight polar pattern are typically rIbbon or Large Diaphragm Microphones.

Bidirectional microphones